Most brake systems for cars and trucks currently have the capability of including anti-skid functions to prevent wheel lock from occurring during a brake application. In such systems, sensors are commonly located at each wheel to detect wheel rotation and when a potential lock up may occur, a signal is sent to an electronic control unit such that the pressure presented to the individual wheel brake is modulated and as a result wheel lock up may be avoided. The types of sensors used in a brake system vary and can be selected from a variety of devices such as variable reluctance devices commonly referred to as a passive sensors, Hall effect devices, AMR effect devices, GMR effect devices commonly referred to as active sensors, etc. . . . A sensor is usually activated by a magnetic field coupling relationship through some type of exciter ring, slotted disc, magnetized encoder, or other component that rotates with the wheel. The space relationship between the sensor and the activator is an important feature as disclosed in U.S. Pat. Nos. 5,011,302 and 5,129,741 wherein the tone wheel is respectively located on the hub adjacent to the sensor. This type of relationship is satisfactory for most applications, but under some circumstances it may be possible to damage or obstruct the sensor and exciter and as a result the signal sent to the electronic control unit might be inaccurate in controlling a brake application.